Receive the latest national-international updates in your inbox

The sand on Siesta Beach on Florida's Gulf Coast is as fine as powdered sugar, a pure, sparkling white and soft as a kitten's fur — all because it's comprised of 99 percent pure crushed quartz.

For that reason, and many others, it was selected this year as the best beach in America by a professor who's made a career ranking and studying beaches around the United States.

"The sand is outstanding," said Stephen Leatherman, aka Dr. Beach, a professor at Miami's Florida International University. "Every time I go there, I've got to take a bag home with me. It's almost sacrilegious to walk on it with shoes on."

Other beaches that made the list this year, in order of ranking, are: Kapalua Bay Beach in Maui, Hawaii; Ocracoke Lifeguarded Beach on the Outer Banks of North Carolina; Grayton Beach State Park on the Florida Panhandle; Coopers Beach in Southampton, New York; Coast Guard Beach on Cape Cod in Massachusetts; Caladesi Island State Park in Dunedin/Clearwater, Florida; Hapuna Beach State Park, Big Island, Hawaii; Coronado Beach in San Diego, California; and Beachwalker Park on Kiawah Island, South Carolina.

U.S. territories like Puerto Rico and the Virgin Islands aren't included in the rankings.

On a recent workday, Siesta Beach was packed with people, even though it wasn't particularly sunny. The turquoise water was still gorgeous, the sand still fine. The beach is about 200-300 feet (60-90 meters) wide in some places, which means people can stretch out and not feel crowded. The beach was last year's runner up and one of three in Florida on this year's top 10 list.

"It's nice and clean, that's what I look for," said Jamie Gaskin, a 59-year-old retiree from Lakeland, Florida, who was scoping out the beach for a family Memorial Day party. She especially liked the two-story pavilion, which boasts a snack bar and restrooms. It's only two years old and even offers sweet crepes for breakfast and tapas dishes in the early evening.

"There's plenty of tables to barbecue and to hang out. And the restrooms were nice and clean. I'd definitely recommend this," she said.

Siesta Beach is on a barrier island in the Gulf of Mexico, and is located just southwest of downtown Sarasota. The water is placid on most days — Leatherman says you can measure the waves "in inches" — and is shallow and safe for swimming, with no sharp drop-offs. Added bonuses include lots of parking, a trolley service to and from the island's adorable downtown area and plenty of lifeguards. The beach also has natural dunes, which is a bit rare for Florida, and the fine sand is excellent for building sand castles.

"I look for kind of a balance between nature and a developed environment," said Leatherman, who lives on the other side of the state, closer to Miami Beach. "Fourteen million people go to Miami Beach every year. There's just too many people there. I think a lot of people are looking for more of a getaway."

Leatherman, who is director of the Laboratory for Coastal Research at Florida International University, uses about 50 criteria to assess and rank beaches across the country. In recent years, he has given extra points to beaches that prohibit smoking, saying cigarette butts are not only environmentally damaging, but can ruin the experience for beach-goers. Safety and environmental management are other major factors, he said.

He's rated beaches since 1991.

The Maui beach that came in at No. 2 on the list, Kapalua Bay Beach, is smaller than Siesta Beach. It's crescent-shaped and flanked by palm trees. Unlike lots of Hawaii beaches, there aren't many waves at Kapalua, he said, making it perfect for safe swimming.

Leatherman says he tries to select locations that are a bit off the beaten path, yet immensely rewarding once visitors arrive. Siesta Beach, he points out, is an outstanding place to watch the sun dip below the Gulf horizon — one more reason why it made the top of this year's list.

Published at 10:07 AM EDT on May 25, 2017 | Updated at 7:32 AM EDT on May 26, 2017